The present invention concerns packaging according to the preamble to claim 1.
Packaging of this type is known, as disclosed, for example, in U.S. Pat. No. 5,728,414. In particular, FIG. 4 of this patent illustrates packaging comprising two ovoid half-shells made from plastics material, one containing an edible product and the other containing an accessory such as, for example, a so-called "surprise". At least one of the half-shells is closed by a cover in the form of a sheet-like diaphragm attached to the mouth part of the half-shell itself. The two half-shells are then connected together in a face-to-face relationship to form a generally egg-shape shape packaging.
The two half-shells are provided with mutually off-set, projecting tongues in correspondence with the flanged edges which enable their coupling. These tongues can be grasped by the user in order to separate the half-shells. Where the half-shell is closed by a sheet, the associated tongue is--as it were--double, in that it is present both on the mouth edge of the half-shell as well as--in an exactly corresponding position--on the sealing sheet. In a manner substantially similar to the operation for separating the half-shells described above, the user can separately grasp the tongue on the half-shell and the tongue on the sheet and pull on them directly in order to detach the sealing sheet from the mouth edge of the half-shell.
The Applicant has been able to show that the preceding arrangement, although fully satisfactory, can be further improved in various ways.
In the first place, it is necessary to ensure that the sequence of operations for opening the packaging always occurs in the order described above.
It is thus necessary to avoid, for example, the sealing sheet of the half-shell containing the food product becoming detached from the associated half-shell before the half-shells themselves are separated. The same problem arises in the case of a further possible embodiment in which both half-shells of the packaging are closed by associated sealing sheets.
It is also desirable, even though the separation of the two half-shells occurs first, to avoid this giving rise to unwanted detachment, even partial detachment, of the sealing sheet of the half-shells, in particular, of the half-shell containing the edible product. Packaging such as that described in U.S. Pat. No. 5,728,414 is, in fact, intended primarily for young consumers who often attempt immediately to open the half-shell containing the surprise, leaving the consumption of the edible product in the other half-shell until later. This half-shell may therefore be put to one side, at least momentarily, for example, by putting it in a pocket. The possible at least partial detachment of the associated seal may give rise to the unwanted escape of the edible product from the regions where the associated sealing sheet has become detached.
General hygienic requirements make it preferable for the half-shell containing the edible product to remain sealed until the user positively opens it by removing the associated sealing sheet in order to consume the edible product. The same considerations apply substantially to the other half-shell containing the surprise, it being preferable that the consumer is able initially to separate the two half-shells without having to worry about the surprise immediately falling out. For this reason, it is usually preferred that the half-shell containing the surprise, like the half-shell containing the edible product, also has an associated sealing sheet. In this way, once the two half-shells are separated, the user (usually of young age) is able calmly to proceed to open the half-shell containing the surprise, holding the half-shell facing upwards in the palm of one hand and removing the sealing sheet with the other hand. This method significantly reduces the risk of the surprise accidentally falling out.
It has also been shown that locating off-set tongues on the two half-shells can cause an unwanted rotation of the packaging while the two half-shells are being separated.
The need to ensure a predetermined sequence for the separation of the various component parts of the packaging (half-shells and associated sealing sheets) could be at least substantially resolved by markedly differentiating the connecting forces between the various parts. At least in theory, for example, the face-to-face connection between the two half-shells could be made such that the connection between corresponding half-shells is weaker than the connection to or between each sheet. To be truly effective, such a differentiation would carry a serious risk of leading to the unwanted separation of the half-shells before the user wishes effectively to open the packaging in order to consume the product or--on the other hand--to a connection force between the sealing sheet and the half-shell that would make it difficult to detach the sheet from the half-shell. In relation to this latter aspect, it should be taken into account that, on the one hand, the user is frequently a very young person who is unable to exert a significant force with his or her hands and, on the other hand, the application of a very decisive force in the separation operation can lead to the unwanted deformation of the half-shell.
In relation to this, it has been shown that the methods of connection usable in this particular context (the half-shells and sealing sheets in question usually being formed from plastics material) do not generally allow, given the high production rates, a very close graduation in the resistance to separation to be achieved from the connection action. This consideration is particularly applicable to heat sealing techniques.
The object of the present invention is to provide an arrangement capable of satisfying in an excellent manner all of the requirements outlined above.
According to the present invention, this object is achieved by virtue of packaging having the characteristics set out in the following claims. The invention also concerns the associated manufacturing process.